Retrospective analysis of veno-occlusive disease/sinusoidal obstruction syndrome in paediatric patients undergoing hematopoietic cell transplantation -a multicentre study.

Background: Sinusoidal obstruction syndrome is a potentially fatal complication following hematopoietic cell transplantation, high-intensity chemotherapies and increasingly seen with calicheamicin based leukemia therapies. Paediatric specific European Society for Blood and Marrow Transplantation (pEBMT) diagnostic criteria have demonstrated benefit in single center studies compared to historic criteria. Yet, the extent to which they have been universally implemented remains unclear. Methods: We conducted a retrospective multi-centre study to examine the potential impact of the Baltimore, modified Seattle and pEBMT criteria on the incidence, severity, and outcomes of sinusoidal obstruction syndrome among paediatric hematopoietic cell transplantation patients. Findings: The incidence of sinusoidal obstruction syndrome in this cohort (n = 488) was higher by pEBMT (21.5%) vs historic modified Seattle (15.6%) and Baltimore (7.0%) criteria (p < 0.001). Application of pEBMT criteria identified 44 patients who were not previously diagnosed with sinusoidal obstruction syndrome. Overall, 70.5% of all patients diagnosed with sinusoidal obstruction syndrome ultimately developed very severe disease and almost half of diagnosed patients required critical care support. Overall survival was significantly lower in patients who were diagnosed with sinusoidal obstruction syndrome vs those who were not. Interpretation: Taken together, pEBMT criteria may be a sensitive method for prompter diagnosis of patients who subsequently develop severe/very severe sinusoidal obstruction syndrome. To our knowledge, this is the first multi-centre study in the United States (US) to demonstrate that pEBMT guidelines are associated with earlier detection of sinusoidal obstruction syndrome. Since early initiation of definitive treatment for sinusoidal obstruction syndrome has been associated with improved survival in paediatric patients and implementation of pEBMT criteria appears feasible in the US, universal adoption should facilitate prompter diagnosis and lead to improved outcomes of children with sinusoidal obstruction syndrome. Funding: None.

A phase I trial of the pan-ERBB inhibitor neratinib combined with the MEK inhibitor trametinib in patients with advanced cancer with EGFR mutation/amplification, HER2 mutation/amplification, HER3/4 mutation or KRAS mutation.

PURPOSE: Aberrant alterations of ERBB receptor tyrosine kinases lead to tumorigenesis. Single agent therapy targeting EGFR or HER2 has shown clinical successes, but drug resistance often develops due to aberrant or compensatory mechanisms. Herein, we sought to determine the feasibility and safety of neratinib and trametinib in patients with EGFR mutation/amplification, HER2 mutation/amplification, HER3/4 mutation and KRAS mutation. METHODS: Patients with actionable somatic mutations or amplifications in ERBB genes or actionable KRAS mutations were enrolled to receive neratinib and trametinib in this phase I dose escalation trial. The primary endpoint was determination of the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT). Secondary endpoints included pharmacokinetic analysis and preliminary anti-tumor efficacy. RESULTS: Twenty patients were enrolled with a median age of 50.5 years and a median of 3 lines of prior therapy. Grade 3 treatment-related toxicities included: diarrhea (25%), vomiting (10%), nausea (5%), fatigue (5%) and malaise (5%). The MTD was dose level (DL) minus 1 (neratinib 160 mg daily with trametinib 1 mg, 5 days on and 2 days off) given 2 DLTs of grade 3 diarrhea in DL1 (neratinib 160 mg daily with trametinib 1 mg daily). The treatment-related toxicities of DL1 included: diarrhea (100%), nausea (55.6%) and rash (55.6%). Pharmacokinetic data showed trametinib clearance was significantly reduced leading to high drug exposures of trametinib. Two patients achieved stable disease (SD) ≥ 4 months. CONCLUSION: Neratinib and trametinib combination was toxic and had limited clinical efficacy. This may be due to suboptimal drug dosing given drug-drug interactions. TRIAL REGISTRATION ID: NCT03065387.

Inhibition of the Phosphatidylinositol-3 Kinase Pathway Using Bimiralisib in Loss-of-Function NOTCH1-Mutant Head and Neck Cancer.

BACKGROUND: PI3K/mTOR inhibition leads to apoptosis of NOTCH1-mutant head and neck squamous cell carcinoma (HNSCC) cells. We tested the efficacy of the PI3K/mTOR inhibitor bimiralisib in patients with NOTCH1-mutant HNSCC. METHODS: Patients with recurrent/metastatic NOTCH1-mutant HNSCC who had progressed during chemotherapy and immunotherapy received bimiralisib until unacceptable toxicity or progression. To assess whether NOTCH1 mutations can be detected in blood, we measured circulating tumor DNA (ctDNA). To assess activated NOTCH1 protein levels, we quantitated cleaved NOTCH1 (cl-NOTCH) by immunohistochemistry. RESULTS: Eight patients were treated, and 6 were evaluable for response. The objective response rate was 17%. For all 8 patients, median progression-free and overall survival was 5 and 7 months, respectively. Bimiralisib was well tolerated, with expected hyperglycemia. Pharmacokinetic values were consistent with published studies. NOTCH1 mutations were detected in 83.3% of ctDNA. Staining for tumor cl-NOTCH1 was negative. The trial closed early due to sponsor insolvency. CONCLUSION: Although the trial was small, outcomes with bimiralisib were better than the historical standard of care; Results will need to be confirmed in a larger trial. The lack of cl-NOTCH1 was consistent with loss-of-function mutations and validated our mutation function algorithm. The ability to detect NOTCH1 mutations in blood will help future studies. (ClinicalTrials.gov Identifier: NCT03740100).

Targeting the mTOR Pathway for the Prevention of ER-Negative Breast Cancer.

PREVENTION RELEVANCE: Our results show that everolimus delays mammary tumor formation in multiple mouse models, suggesting that mTOR inhibitors will be useful for the prevention of ER-negative and triple-negative breast cancer in humans. See related Spotlight, p. 787.

Vorinostat Combined with Busulfan, Fludarabine, and Clofarabine Conditioning Regimen for Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Acute Leukemia: Long-Term Study Outcomes.

Conditioning regimens play a major role in determining disease outcomes following allogeneic hematopoietic stem cell transplantation (allo-HSCT). The use of i.v. busulfan (Bu) as part of conditioning chemotherapy has been shown to be effective in controlling disease relapse; however, disease relapse remains a major cause of death following allo-HSCT. This study was conducted to determine the long-term outcomes of vorinostat with i.v. Bu plus dual nucleoside analogs clofarabine (Clo) and fludarabine (Flu) in the conditioning regimen for patients undergoing allo-HSCT. This was a rapid dose escalation phase I/II study designed to determine whether the addition of vorinostat would improve the efficacy of standard i.v. Bu/Flu/Clo conditioning regimen. This report presents the long-term disease outcomes of this combination in 68 patients with high-risk leukemia, including 31 (46%) with acute lymphoblastic leukemia (ALL) and 37 (54%) with acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS). Fifty-eight patients (85%) were in morphologic complete remission at time of transplantation, and 38 (56%) received a matched unrelated donor graft. Over the median follow-up of 37.6 months, 29 of the 68 patients died (43%), and the nonrelapse mortality (NRM) rate was 22% (n = 15). The median overall survival and median NRM were not reached. Nineteen patients (28%) experienced disease progression. The median progression-free survival was 36.8 months. Thirty-seven patients (57%) developed grade II-IV acute graft-versus-host disease (GVHD), and 20 patients (31%) developed chronic GVHD. Our results suggest a lack of benefit from adding a short course of vorinostat to i.v. Bu/Flu/Clo conditioning regimens for leukemia patients undergoing allo- HSCT.

A randomized phase III study of pretransplant conditioning for AML/MDS with fludarabine and once daily IV busulfan ± clofarabine in allogeneic stem cell transplantation.

Pretransplant conditioning with Fludarabine (Flu)-Busulfan (Bu) is safe, but clofarabine (Clo) has improved antileukemic activity. Hypothesis: Flu+Clo-Bu (FCB) yields superior progression-free survival (PFS) after allogeneic transplantation. We randomized 250 AML/MDS patients aged 3-70, Karnofsky Score ≥80, with matched donors, to FCB (n = 120) or Flu-Bu (n = 130), stratifying complete remission (CR) vs. No CR, (NCR). HCT-CI scores varied, from 0 to 10. All evaluable patients engrafted. Median follow-up was 66 months (interquartile range: 58-80). Three-year relapse incidence (RI), 25% with FCB, vs. 39% with Flu-Bu (p = 0.018), offset by higher non-relapse mortality, 22.6% (95%CI: 16-30.2%) vs. 12.3% (95%CI: 6.5-19%). Three-year PFS was 52% (95%CI: 44-62%) (FCB), vs. 48% (95%CI: 41-58%) (Flu-Bu). FCB benefited CR patients less, NCR patients age ≤ 60 had 3-year 34% RI (95%CI: 19-49%) (FCB) vs. 56% (95%CI: 38-70%) after Flu-Bu (p = 0.037). NCR patients >60 years had 3-year RI 10.0% (FCB), vs. 56.0%, after Flu-Bu (p = 0.003). Bayesian regression analysis including treatment-covariate interactions showed FCB superiority in NCR patients with low HCT-CI (0-2). Serious adverse event profiles were similar for the regimens. Conditioning with FCB did not improve PFS overall, but improved disease control in NCR patients, mandating confirmatory trials. Remission status and HCT-CI should be considered when using FCB.

Stability of Captisol-enabled versus propylene glycol-based melphalan at room temperature and after refrigeration.

PURPOSE: To compare the chemical stability of Captisol-enabled (CE) melphalan ("CE-melphalan"; Evomela, Acrotech Biopharma LLC) and propylene glycol (PG)-based melphalan ("PG-melphalan"; Alkeran, GlaxoSmithKline) admixtures prepared with 0.9% sodium chloride injection in polyvinyl chloride (PVC) bags or reconstituted vials stored at room temperature (RT) and under refrigeration. METHODS: Lyophilized CE-melphalan and generic PG-melphalan were reconstituted to 5 mg/mL with 0.9% sodium chloride injection or manufacturer-supplied diluent, respectively. The reconstituted vials were then diluted to the desired concentrations with 0.9% sodium chloride injection in PVC bags and were stored at RT (23oC) or under refrigeration (4oC). Aliquots were withdrawn from the bags and reconstituted vials of CE-melphalan and PG-melphalan immediately after preparation and at predetermined time intervals. Melphalan concentrations were measured using a validated high-performance liquid chromatography method. RESULTS: CE-melphalan reconstituted in PVC bags at concentrations of 1 and 2 mg/mL was stable for 6 and 24 hours, respectively, at RT and for 8 and 24 hours, respectively, at 4oC. PG-melphalan reconstituted in bags at 1, 1.5, and 2 mg/mL was stable for 1, 2, and 2 hours, respectively, at RT and for 2, 4, and 4 hours, respectively, at 4oC. Reconstituted CE-melphalan vials were stable for 48 hours at both RT and 4oC, whereas PG-melphalan vials were stable for 6 hours at RT but formed precipitate within 2 hours at 4oC. CONCLUSION: CE-melphalan remained stable longer than generic PG-melphalan under the test conditions. CE-melphalan at 2 mg/mL has 24-hour stability at RT and can be used for extended infusion times or may be compounded ahead of time. Reconstituted CE-melphalan vials are stable for 48 hours at both RT and 4oC.

Phase I Trial of Definitive Concurrent Chemoradiotherapy and Trametinib for KRAS-Mutated Non-Small Cell Lung Cancer.

OBJECTIVE: This phase I trial (NCT01912625) evaluated the safety and pharmacokinetics of definitive concurrent chemoradiotherapy (cCRT) and the radiosensitizer trametinib (MEK1/2 inhibitor) for KRAS-mutated nonmetastatic non-small cell lung cancer (NSCLC). METHODS: Patients received cCRT (carboplatin/paclitaxel and 60 Gy/30 fractions radiotherapy); oral trametinib (7 days/week) commenced on day 1 and completed on the final day of radiotherapy. Dose-finding of trametinib was done using the time-to-event continual reassessment method (TiTE-CRM); dose levels were 0.5mg (level -1), 1mg (initial, level 1), 1.5mg (level 2), and 2mg (level 3). Progression-free (PFS) and overall survival (OS) times were also recorded. RESULTS: Fifteen patients (stage III, variety of KRAS mutations) were treated, with 1/5/4/5 at dose levels -1/1/2/3, respectively. Five patients received dose reductions (n=2, levels 2 and 3; n=1, level 1). Twelve patients completed the full cCRT course. One patient (following 12d trametinib) was taken off protocol for an unrelated/unresolved grade 1 event and later experienced grade 5 sepsis/respiratory failure. There was one grade 4 retinal detachment; grade 3 events included skin rash (n=2) and ventricular dysfunction, pneumonitis, pain, fatigue, and diarrhea (n=1 each). The final dose selected by the TiTE-CRM of trametinib was 1.5 mg. Pharmacokinetic profiles were elucidated and extensively described. At median follow-up of 70 months, median PFS was 11 months and median OS was 38 months. CONCLUSIONS: The MTD for trametinib when combined with cCRT is 1.5 mg, with encouraging preliminary outcomes. This combination merits further study to combine with consolidation durvalumab in non-metastatic KRAS mutant NSCLC.

Chemical Degradation of Intravenous Chemotherapy Agents and Opioids by a Novel Instrument.

Purpose: To assess chemical degradation of various liquid chemotherapy and opioid drugs in the novel RxDestruct™ instrument. Methods: Intravenous (IV) drug solutions for chemotherapy and pain management were prepared using 0.9% normal saline in Excel® bags to a final volume of 500 mL. We investigated duplicate IV solutions of methotrexate (0.1 mg/mL), etoposide (0.4 mg/mL), doxorubicin (0.25 mg/mL), cladribine (12.4 µg/mL), fentanyl (1.0 µg/mL), and hydromorphone (12.0 µg/mL) in this study. Solutions were poured into an automated instrument to undergo pulsatile chemical treatment (Fenton reactions) for 20 minutes, and then discharged from the instrument through a waste outlet. Extent of intact drug degradation was determined by measuring concentrations of drugs before entry into the instrument and after chemical treatment in the filtrate using high-performance liquid-chromatography with ultraviolet detection (HPLC-UV). Results: Following chemical reactions (Fenton processes) in the automated instrument, infusion solutions containing methotrexate, etoposide, doxorubicin, and cladribine had levels below the HPLC-UV limit of quantification (LOQ), indicating <50 ppb of each. This equated to >99.5%, 99.99%, 99.9%, and 99.8% intact drug loss, respectively. Likewise, processed samples of fentanyl and hydromorphone contained levels below the LOQ (78 and 98 ng/mL, respectively), indicating extensive degradation (>92.2% and 99.2% intact drug loss, respectively). Conclusion: The novel instrument was capable of degrading intact chemotherapy and opioid drugs prepared in infusion solutions to undetectable quantities by HPLC-UV. RxDestruct™ is a possible alternative for disposal of aqueous medication waste.

Asparaginase-Associated Pancreatitis in Pediatric Patients with Acute Lymphoblastic Leukemia: Current Perspectives.

Asparaginase therapy is a vital agent in the treatment of acute lymphoblastic leukemia (ALL), with increasing evidence of its high importance in high-risk ALL populations. However, despite the clear clinical and biological benefits of asparaginase therapy, many patients experience toxicities. A well-known treatment-limiting toxicity is asparaginase-associated pancreatitis (AAP). If severe, it necessitates discontinuation of asparaginase therapy, which can lead to a higher risk of relapse in patients with ALL. New protocols for ALL therapy have increased overall total doses of asparaginase therapy in select high-risk populations and have incorporated longer half-life formulations of pegylated asparaginase. Treatment drug monitoring has also allowed assurance of adequate levels of asparagine depletion throughout treatment. It is currently unknown if these changes will increase rates of AAP. Interestingly, important pharmacogenomics data, such as single nucleotide polymorphisms, can identify patients at the highest risk for severe AAP. The incidence of AAP in recent trials, current pharmacogenomic data that could further our understanding of the disease, and the importance of cautiously re-exposing patients to further asparaginase treatment after an initial episode of AAP are discussed.

Myeloablative Fractionated Busulfan With Fludarabine in Older Patients: Long Term Disease-Specific Outcomes of a Prospective Phase II Clinical Trial.

Compared to reduced-intensity conditioning regimen, myeloablative conditioning (MAC) for hematopoietic stem cell transplantation (HCT) reduces relapse but is avoided in older patients because of higher non-relapse mortality (NRM). To meet the need for a myeloablative regimen for older patients, we developed a novel fludarabine and busulfan MAC regimen. We fractionated the dose of busulfan and gave it for 6 days over a 2-week period and demonstrated the feasibility and safety of this approach. However, the disease-specific efficacy of this regimen is not known. The purpose of this study was to estimate the efficacy of fractionated busulfan regimen by estimating diseases specific survival outcomes. The conditioning regimen consisted of busulfan and fludarabine. On days -13 and -12 before HCT, patients received 80 mg/m2 busulfan intravenously (IV) daily in an outpatient clinic. Additional chemotherapy was administered during inpatient treatment from day -6 through day -3, including fludarabine 40 mg/m2 and busulfan IV once daily. The dosing of busulfan was determined from pharmacokinetic analyses to achieve for the course a target area under the curve of 20,000 ± 12% µmol/min, which is close to the average exposure of myeloablative dose of busulfan. One hundred fifty patients with high-risk hematological malignancies up to 75 years were enrolled in this prospective phase II study. The objective was to evaluate NRM, relapse, survival, the rates of graft-versus-host disease (GVHD), and long-term complications. The median age of the patient population was 61 years (interquartile range, 55-67). The most common diagnoses were acute myeloid leukemia (AML; N = 59 [39.3%]), myelodysplastic syndrome (MDS; n = 29 [19.3%]), and myelofibrosis (MF; N = 22 [14.7%]). Most had an unrelated donor (n = 93 [62%]) and received peripheral blood graft (n = 110 [73.3%]). Over half had an HCT-specific comorbidity index of ≥3 (n = 79 [52.7%]). The median follow-up among survivors was 43.4 months (interquartile range, 38.9-50.4). In patients with AML in complete remission, MDS, and myelofibrosis, 3-year overall survival was 66.7% (95% confidence interval [CI], 50.2-88.5%), 43.6% (95% CI, 28.6-66.4%), and 59.1% (95% CI, 41.7-83.7%) respectively. The cumulative incidence of NRM was 22% (15.3%-28.7%), extensive chronic GVHD was 27% (95% CI, 20-34%), bronchiolitis obliterans was 4.7% (95% CI, 1.3-8.1%), and secondary malignancy was 8.7% (95% CI, 4.1-13.2%) at 3 years. Lengthening the duration of busulfan (fractionation) permits safe delivery of myeloablative conditioning in older patients, leading to prolonged survival. © 2021 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

A rare case of methotrexate and primaquine co-administration in a mantle cell lymphoma patient.

WHAT IS KNOWN AND OBJECTIVE: High-dose methotrexate (HD-MTX) is associated with a plethora of adverse drug reactions and potential drug interactions (DIs). But there is a paucity of information regarding the safety of co-administering primaquine with HD-MTX. CASE SUMMARY: A 65-year-old male patient was diagnosed with mantle cell lymphoma (MCL) with CNS involvement and treated with three cycles of IV HD-MTX. His case was further complicated by fungal pneumonia treated with primaquine during cycle-2. Serial blood sampling and subsequent population pharmacokinetics (PK) modelling suggests a possible distribution-mediated DI between the two drugs. WHAT IS NEW AND CONCLUSION: This is the first case report to highlight the safe co-administration of MTX and primaquine, despite a possible PK interaction.

Pharmacokinetics: Unique Challenges in Blood Monitoring for Oncology Nurses.

BACKGROUND: Pharmacokinetics (PK) is the study of the absorption, distribution, metabolism, and excretion of drugs. Many chemotherapeutic agents have a sensitive PK index, in which a small margin in blood concentrations is the difference between nontherapeutic, therapeutic, and adverse outcomes. OBJECTIVES: This article will provide an overview of evidence-based approaches to the collection of PK samples, monitoring of PK levels, and the resulting management of patients undergoing PK testing. METHODS: A case study involving busulfan, an alkylating agent used in the pre-stem cell transplantation setting, will highlight the cross-contamination of samples while a drug is being infused through a central venous catheter with PK sample collection from a proximal peripherally inserted central catheter. The influence of false elevations in drug concentrations on PK-guided dose adjustments will also be emphasized. FINDINGS: Imprecise blood collections or cross-contamination of samples may lead to inaccurate drug concentration results and, subsequently, undesired low or high drug dosage calculations.

Conditioning with busulfan plus melphalan versus melphalan alone before autologous haemopoietic cell transplantation for multiple myeloma: an open-label, randomised, phase 3 trial.

BACKGROUND: Retrospective studies suggest that conditioning therapy with busulfan plus melphalan could result in longer progression-free survival compared with melphalan alone in patients with multiple myeloma undergoing autologous haemopoietic cell transplantation (auto-HCT). We aimed to test this hypothesis in a randomised trial. METHODS: The primary objective of the study was to compare progression-free survival with conditioning of busulfan plus melphalan with melphalan alone in patients with multiple myeloma. Patients with newly diagnosed multiple myeloma who were eligible for cell transplantation, aged 70 years or younger, with at least stable disease, were randomly assigned (1:1) to treatment. Patients received either busulfan plus melphalan, with a test dose of busulfan 32 mg/m2 followed by pharmacokinetically adjusted doses on days -7, -6, -5, and -4 to achieve a target daily area under the curve (AUC) of 5000 mmol-minute and melphalan 70 mg/m2 per day on days -2 and -1 (total melphalan dose 140 mg/m2), or a melphalan dose of 200 mg/m2 on day -2. Randomisation was performed via a Clinical Trial Conduct Website at the University of Texas MD Anderson Cancer Center. The accrual is complete and final results are presented here. The study is registered with ClinicalTrials.gov, number NCT01413178. FINDINGS: Between Oct 12, 2011, and March 22, 2017, 205 patients were assessed for eligibility and randomly assigned to treatment. The primary analysis of progression-free survival was measured in 202 patients who received treatment: 104 patients in the busulfan plus melphalan group and 98 patients in the melphalan alone group. 90 days after auto-HCT, 102 (98%) of 104 patients given busulfan plus melphalan and 95 (97%) of 98 patients given melphalan alone achieved partial response or better. The median follow-up in the busulfan plus melphalan group was 22·6 months (IQR 15·2-47·1) and 20·2 months (IQR 8·8-46·6) in the melphalan alone group. Median progression-free survival was 64·7 months (32·9-64·7) with busulfan plus melphalan versus 43·5 months (19·9-not estimated) with melphalan alone (hazard ratio 0·53 [95% CI 0·30-0·91]; p=0·022). There were no treatment-related deaths by day 100 in either group. Grade 2-3 mucositis was observed in 77 (74%) of 104 patients in the busulfan plus melphalan group versus 14 (14%) of 98 patients in the melphalan alone group. INTERPRETATION: These findings, if confirmed in other ongoing studies, suggest that busulfan plus melphalan could replace melphalan alone as the conditioning regimen for auto-HCT in patients with newly diagnosed myeloma. FUNDING: This study was funded in part by the National Institutes of Health (NIH) through MD Anderson's Cancer Center Support Grant (CA016672).

Fludarabine with a higher versus lower dose of myeloablative timed-sequential busulfan in older patients and patients with comorbidities: an open-label, non-stratified, randomised phase 2 trial.

BACKGROUND: Haemopoietic stem-cell transplantation (HCT) conditioning regimens that can reduce risk of relapse without increasing non-relapse mortality are needed. We aimed to test the safety of timed-sequential delivery of low-dose versus high-dose myeloablative busulfan in older patients and patients with comorbidities. METHODS: This non-stratified, open-label, randomised phase 2 trial was done at The University of Texas MD Anderson Cancer Center (Houston, TX, USA). Patients with haematological cancers aged between 5 and 75 years were eligible to participate in the study. Patients who had HIV or uncontrollable infections were excluded. Eligible patients were randomly assigned (1:1 by a computer-generated programme in block sizes of four) to receive a total intravenous busulfan dose to achieve an area under the curve of 16 000 µmol/min (16K group) or 20 000 µmol/min (20K group) on the basis of pharmacokinetic analysis, plus intravenous fludarabine 40 mg/m2 for 4 days. The investigators and the research nurses were masked to the block size to conceal allocation. The primary outcome was day 100 non-relapse mortality. All analyses were by modified intention to treat, including only patients who received at least one dose of the study drug. No interim analyses were planned and accrual is complete. This study is registered with ClinicalTrials.gov, number NCT01572662. FINDINGS: Between April 18, 2012, and Dec 9, 2015, 98 patients were enrolled. 49 patients were randomly assigned to the 16K group and 49 to the 20K group, one of which was removed from the study before starting the intervention. Median age was 60 years (IQR 54-67). 50 (52%) patients had an HCT-specific comorbidity index score of 3 or more, and 41 (42%) had a high or very high Disease Risk Index score. Day 100 non-relapse mortality was 4% (95% CI 0-10) in the 16K group and 6% (0-13) in the 20K group (p=0·65). Infection was the most common grade 3-5 toxicity in both the 20K group (25 [52%] of 48 patients) and the 16K group (24 [49%] of 49 participants). Mucositis (nine [19%] of 48 patients vs three [6%] of 49 patients), idiopathic pneumonia syndrome (nine [19%] of 48 patients vs two [4%] of 49 patients), and culture-negative neutropenic fever (16 [33%] of 48 patients vs eight [16%] of 49 patients) were more common in the 20K group than in the 16K group. INTERPRETATION: Myeloablative doses of busulfan administered in a timed-sequential manner with fludarabine is associated with low non-relapse mortality in older patients and patients with comorbidities. Additional studies are required to show whether this approach can reduce the risk of relapse. FUNDING: Cancer Center Support Grant (US National Cancer Institute, National Institutes of Health).

Aerosol Gemcitabine after Amputation Inhibits Osteosarcoma Lung Metastases but Not Wound Healing.

BACKGROUND: In newly diagnosed osteosarcoma (OS) patients, the time between surgery and resumption of chemotherapy is 2-7 weeks. Delays > 16 days are associated with increased risk of relapse and decreased overall survival. Identifying an effective therapy that can be used postoperatively may prevent relapse. We investigated whether aerosol gemcitabine (GCB) initiated after tumor resection inhibited the growth of OS lung metastases without affecting the wound-healing process. METHODS: Mice were injected intratibially with OS cells. Amputation was performed when the tumor reached 1.5 cm. Full-thickness excisional wounds were also made on the dorsal skin and tail. Aerosol GCB or PBS was initiated 48 hours after amputation (3 times/week for 3 weeks). Wound sections were evaluated by immunohistochemistry for Ki-67 (proliferation), CD31 (vessels), VEGF, IL-10, bFGF, mast cells, macrophages, and M1/M2 macrophage ratios. The lungs were analyzed for macro- and micrometastases. RESULTS: Aerosol GCB inhibited the growth of the lung metastases but had no effect on the 3 phases of wound healing in the dorsal skin, tail, or bone. Production of cytokines at the wound sites was the same. CONCLUSION: These data indicate that initiating aerosol GCB postoperatively may kill residual lung metastases thereby preventing relapse and improve survival.

Clarifying busulfan metabolism and drug interactions to support new therapeutic drug monitoring strategies: a comprehensive review.

INTRODUCTION: Busulfan (Bu) is an alkylating agent with a limited therapeutic margin and exhibits inter-patient variability in pharmacokinetics (PK). Despite decades of use, mechanisms of Bu PK-based drug-drug interactions (DDIs), as well as the negative downstream effects of these DDIs, have not been fully characterized. Areas covered: This article provides an overview of Bu PK, with a primary focus on how known and potentially unknown drug metabolism pathways influence Bu-associated DDIs. In addition, pharmacogenomics of Bu chemotherapy and Bu-related DDIs observed in the stem cell transplant clinic (SCT) are summarized. Finally the increasing importance of Bu therapeutic drug monitoring is highlighted. Expert opinion: Mechanistic studies of Bu metabolism have shown that in addition to GST isoenzymes, other oxidative enzymes (CYP, FMO) and ABC/MDR drug transporters likely contribute to the overall clearance of Bu. Despite many insights, results from clinical studies, especially in polypharmacy settings and between pediatric and adult patients, remain conflicting. Further basic science and clinical investigative efforts are required to fully understand the key factors determining Bu PK characteristics and its effects on complications after SCT. Improved TDM strategies are promising components to further investigate, for instance DDI mechanisms and patient outcomes, in the highly complex SCT treatment setting.

Solubilization and Stability of Mitomycin C Solutions Prepared for Intravesical Administration.

BACKGROUND: Mitomycin C (MMC) is an antitumor agent that is often administered intravesically to treat bladder cancer. Pharmacologically optimized studies have suggested varying methods to optimize delivery, with drug concentration and solution volume being the main drivers. However, these MMC concentrations (e.g. 2.0 mg/mL) supersede its solubility threshold, raising major concerns of inferior drug delivery. OBJECTIVE: In this study, we seek to confirm that the pharmacologically optimized MMC concentrations are achievable in clinical practice through careful modifications of the solution preparation methods. METHODS: MMC admixtures (1.0 and 2.0 mg/mL) were prepared in normal saline using conventional and alternative compounding methods. Conventional methodology resulted in poorly soluble solutions, with many visible particulates and crystallates. However, special compounding methods, which included incubation of solutions at 50 °C for 50 min followed by storage at 37 °C, were sufficient to solubilize drug. Chemical degradation of MMC solutions was determined over 6 h using high-performance liquid chromatography (HPLC) analytics, while physical stability was tested in parallel. RESULTS: Immediately following the 50 min incubation, both MMC solutions exhibited approximately 5-7% drug degradation. Based on the measured concentrations and linear regression of degradation plots, additional storage of these solutions at 37 °C for 5 h retained chemical stability criterion (< 10% overall drug loss). No physical changes were observed in any solutions at any test time points. CONCLUSION: We recommend that the described alternative preparation methods may improve intravesicular delivery of MMC in this urological setting, and advise that clinicians employing these changes should closely monitor patients for MMC toxicities and pharmacodynamics (change in clinical outcomes) that result from the potential enhancement of MMC exposure in the bladder.